Madhya Pradesh shares its longest border with which state?

The correct answer is: Chhattisgarh.

Madhya Pradesh shares its longest border with Chhattisgarh, with a total length of 1,001 kilometers. The two states are located in central India and share a common border on the north, east, and south. The border between Madhya Pradesh and Chhattisgarh is mostly defined by the Vindhya Range, a mountain range that runs through central India.

The other options are incorrect for the following reasons:

• Uttar Pradesh is a state in northern India. It shares a border with Madhya Pradesh on the north, but the border is only 550 kilometers long.
• Rajasthan is a state in northwestern India. It shares a border with Madhya Pradesh on the west, but the border is only 992 kilometers long.
• Maharashtra is a state in western India. It shares a border with Madhya Pradesh on the south, but the border is only 720 kilometers long.